ABSTRACT Objective Trauma‐related disorders are experienced by up to 50% of individuals in treatment for an eating disorder, yet research knowledge is limited as to whether trauma‐related symptoms improve during eating disorder treatment. This is particularly true for complex post‐traumatic stress disorder (CPTSD) and its specific symptom domains (PTSD symptoms and disturbances in self organisation [DSO]). Method The current study included 95 individuals with eating disorders who completed measures of trauma‐related symptoms and eating disorder psychopathology at admission, week 4 of treatment, discharge, and 6‐month post‐discharge from residential treatment. Results Linear mixed effects models indicated that both PTSD and DSO symptom domains significantly improved over the course of residential care, adjusting for baseline eating disorder and trauma‐related symptom severity. Change in PTSD symptoms from admission to follow‐up was linear or quadratic, while DSO symptom trajectories exhibited cubic trends such that symptoms were slow to improve early in treatment, showed more rapid improvement later in treatment, and then slightly worsened post‐discharge. Conclusion These findings indicate that symptoms related to both PTSD and CPTSD may improve with eating disorder residential treatment, even without trauma‐focused interventions. However, despite this, trauma‐related symptoms are likely to remain severe post‐treatment. Individuals with this comorbidity may therefore benefit from greater incorporation of trauma‐informed care in specialist eating disorder services as well as trauma‐focused therapies as part of stepdown care. Trial Registration The study was prospectively registered on the Australian and New Zealand Clinical Trials Registry in November 2021, registration number ACTRN12621001651875